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The effect of Si/Al ratio of zeolite Y on the performance of NiW catalysts for second stage hydrocracking was studied. The zeolites were characterized by IR spectroscopy of adsorbed pyridine, low-temperature N2 adsorption, and temperature-programmed desorption of ammonia. The observed decrease of Bronsted and Lewis acid sites concentration relates to the increase of Si/Al ratio in zeolites. According to HRTEM and XPS, sulfide component of catalysts differs in morphology, NiWS phase content and tungsten sulfidation degree. The catalysts were tested in hydrocracking of model (squalane) and real feedstock (unconverted oil (UCO) from two-stage industrial hydrocracker) at different temperatures. The increase of Si/Al ratio in zeolites was found to result in the decrease of catalytic activity and the increase of selectivity to middle distillates. However, similar selectivity of 52 and 53% at the 50% of UCO conversion was observed for catalysts containing zeolites with Si/Al ratio 24 and 37 respectively. This can be attributed mainly to the differences in the textural properties of the zeolites. The catalyst based on amorphous silica-alumina (without zeolites) was found to have a higher selectivity to middle distillates and lower activity as compared to zeolite-based catalysts.

The feasibility of the reactivation of CoMo/Al2O3 hydrotreating catalysts poisoned by Si compounds has been studied. CoMo/Al2O3 catalysts poisoned with 3, 4 and 5 wt.% of silicon were obtained during hydrotreating of diesel fraction contaminated with decamethylcyclopentasiloxane. Catalysts poisoned by different amount of silicon were regenerated by oxidative treatment and subsequently reactivated using citric acid solution. The catalysts were studied by nitrogen adsorption-desorption method, CHNS analysis, UV–vis, thermal analysis, SEM, HRTEM, XPS. It was shown that the hydrodesulfurization activity of regenerated catalysts decreased with increasing silicon content. According to UV–vis results, the increase in Si content on the spent catalyst leads to the formation of CoOx oxides after oxidative regeneration. Probably, cobalt oxides do not promote MoS2 slabs during sulfidation, convert to inactive Co species and decrease hydrodesulfurization activity. After reactivation procedure, there was the increase in active component particles dispersion, while catalytic activity in hydrodesulfurization of dibenzothiophene and hydrodenitrogenation of quinoline increased. It was established that hydrodesulfurization and hydrodenitrogenation activities of CoMo/Al2O3 catalyst with less than 3 wt.% of Si could be completely restored by reactivation.

Data of trawl surveys for the period 2010–2017 revealed distribution of fry saffron cod in vicinity of river outlets, while juvenile walleye pollock was dictributed either near the shore or over the deepwater area in the southern part of shelf. In 2017 aggregations of saffron cod individuals with the body length 29.4–70.5 mm (averaged 52.9 mm) were observed in the area between 52° and 53°N at the depth range 14–195 m. The aggregation densities were maximum at the plots of the highest salinity, temperature and turbidity of the water and higher chlorophyll- a concentration. Principal catches of juvenile walleye pollock were in the area between 53° and 54°N at the depth from 20 to 195 m (averaged 68.2 mm). The aggregation densities of juvenile walleye pollock were maximal at the plots of higher salinity and oxygen concentrations. The concentration of chlorophyll- a was mediate at these plots, comparing to values in the area observed. The body length of the fry varied from 44.5 to 74.6 mm (57.8 mm averaged). Besides juvenile saffron cod and walleye pollock, adult and juvenile individuals of 11 bottom and demersal-pelagic species were found in the catches of the midwater trawl.

In this work, a series of the chromia/alumina catalysts with the same surface Cr concentration of 4.4 ± 0.2 at. Cr/nm2 and different K loadings (0–3.9 wt.%) has been investigated to evaluate the effect of K on the effective activation energy of isobutane dehydrogenation at 520−550 °C. The results of the study show that at K loadings up to 2.0 wt.%, K preferably interacts with alumina and modifies an average dispersion of Cr3+Ox species in the reduced catalysts, thus leading to a growth of conversion and selectivity, but the number of direct contacts of K with active sites is too low to affect the effective activation energy of dehydrogenation. When K loading is higher than 2.0 wt.%, the alumina capacity for K is reached and K interacts directly with Cr3+Ox species. This causes an enlargement of effective activation energy with K loading. One possible explanation relies on the formation of a new type of active sites in Cr3+-O(H)-K+ with modified energetics of the reaction pathway or even with other reaction pathway. Another explanation is that potassium ions, being in contact with active sites, induce strong chemisorption of water, which poisons active sites, especially at low temperatures of the reaction.

NiMo/B-Al2O3 catalysts for VGO hydrotreating differed in peptizing agent for supports preparation (nitric acid or ammonium solution) have been studied. The molar ratio of HNO3/Al2O3 = 0.03 and NH3aqua/Al2O3 = 0.09 and 0.15 were used. Supports and catalysts were studied by the nitrogen and mercury adsorption, IR-spectroscopy of adsorbed CO, XRD, 11B and 27Al NMR, UV–vis DRS, HRTEM, XPS. NiMo/B-Al2O3 catalyst peptized by ammonia at molar ratio of NH3/Al2O3 = 0.09 contains higher amount of NiMoS phase than catalysts peptized by nitric acid. Boron catalyst based support peptized by nitric acid is characterized by active component particles with lower slab length. Simultaneous presence of ammonia and boron results in increase of the slab length of active component, while stacking number decreases. According to the results of catalytic testing in HDS of DBT, boron-containing catalysts are more active. However, NiMo/B-Al2O3 catalyst obtained using ammonia with molar ratio of NH3/Al2O3 = 0.09 has higher activity in HDS of DBT in comparison with NiMo/B-Al2O3 catalyst obtained using nitric acid. Testing in VGO hydrotreating confirmed that utilization of ammonia as a peptizing agent for support preparation significantly improves the activity of boron catalyst in HDS and HDN reactions.

The paper considers the features of modification of wood (pine) with reactive copolymers based on glycidyl methacrylate and fluorine (alkyl) methacrylates to impart water-repellent properties. Such modification provides the achievement of superhydrophobic properties and a decrease in the water permeability of the material due to a smaller spot of contact of water drops with the surface. Wood water absorption index reduced by 3 times.

The article presents the results of a study of the properties of chitosan spongy materials (aerogels) surface modified with copolymers of glycidyl methacrylate. The surface of the obtained materials is characterized by a highly hydrophobic state with contact angles at the initial time moment more than 140 degrees, while a decrease in water absorption of aerogels and a slight decrease in oil absorption are also observed as a result of the modification.

A comparative study of the effect of citric acid (CA), nitrilotriacetic acid (NTA), and diethylene glycol (DEG) used for the preparation of impregnation solution on the properties and catalytic per...

Multi-walled carbon nanotubes (MWCNT) and alumina supported CоMо hydrotreating catalysts prepared with citric acid as a chelating agent (CoMoS/MWCNT-citr and CoMoS/Al2O3-citr respectively) were studied. MWCNT supported catalyst prepared without chelating agent (CoMoS/MWCNT) was also investigated. The addition of citric acid in MWCNT supported catalyst decreases the average slab length of MoS2 from 4.2 to 3.0 nm without increasing the stacking, while the differences in sulfidation degree and MoS2 promotion by cobalt are not observed. The activity of MWCNT-based catalyst in dibenzothiophene hydrodesulfurization (HDS) increases with the addition of citric acid due to improved dispersion of sulfide component. The activity in naphthalene hydrogenation does not change. The results of comparative study of MWCNT and Al2O3 supported catalysts prepared with citric acid show that the catalysts have rather similar morphology of sulfide phase: average slab length of about 3 nm and average stacking number of 1.6-1.7. At the same time, in MWCNT-based catalyst, active metals are sulfided more easily and CoMoS phase is formed at higher extent due to weaker metal-support interaction. CoMoS/MWCNT and CoMoS/Al2O3-citr catalysts are both highly active in HDS and demonstrate similar conversion of dibenzothiophene. The highest HDS activity of CoMo/MWCNT-citr catalyst is attributed to the beneficial effect that is provided by the combined use of carbon support (higher sulfidation degree and higher CoMoS phase content) and citric acid (improved dispersion of sulfide component).

The influence of alumina precursors on catalytic activity CoMoP/Al2O3 hydrotreating catalysts has been studied. Alumina precursors were prepared by eco-friendly technology including hydrothermal treatment at different stabilization time of a flash calcined gibbsite. One sample was synthesized with the addition of boric acid. A reference sample of pseudoboehmite was obtained by precipitation from aluminum nitrate with aqueous ammonia. Alumina precursors, supports and catalysts were studied by XRD, nitrogen adsorption/desorption, XPS, HRTEM. CoMoP/Al2O3 catalysts were tested in hydrotreating of model feed and fuel mixture. It is shown that the samples obtained from the product of flash calcination of gibbsite, besides pseudoboehmite, also include the amorphous phase, while the reference sample, synthesized by precipitation, is a pure pseudoboehmite. The introduction of boron prevents the crystallization of pseudoboehmite. Textural properties of the catalysts depend of initial support: alumina samples prepared by hydrothermal treatment have a bimodal pore distribution with peaks at 60–70 A and 150–200 A, the support synthesized through reprecipitation has a unimodal distribution with a maximum at 80 A. The initial alumina used as a catalyst support has a significant impact on the share of CoMoS phase of type II. The highest activities in the hydrotreating of model feed (dibenzothiophene, quinoline and naphthalene in undecane) and fuel mixture shown catalyst prepared using hydrothermal treatment of flash calcined gibbsite without addition boric acid and with short stabilization time.

We suggest a simple and reproducible strategy for fabricating durable superhydrophobic coatings on the basis of series of functional random copolymers of alkyl methacrylates and glycidyl methacrylate on cotton fabric surface. The procedure consists of the fabric treatment by solutions of copolymers in methylethylketone and following heating at 140 °C. The initial contact angles of obtained coatings on fabric surface achieve 165°. The dependence of superhydrophobic properties of coatings based on copolymers of glycidyl methacrylate and alkyl (meth)acrylates (with alkyl radicals С4–С18 in side chains) attached to the cotton fabric surface was studied. The comparative analysis of superhydrophobic state stability of polymer coatings during long-term contacts with aggressive media is presented. We evaluated the contact angles stability as a function of prolonged contact of polymer coatings with water under saturated vapor conditions, organic solvents, and synthetic detergents. Polymeric coatings based on a copolymer of lauryl methacrylate (С12) and glycidyl methacrylate provide better stability of superhydrophobic properties compared with other copolymers of alkyl methacrylates.

Zeolites of the MTT framework type (Si/Al = 30) have been synthesized using dimethylformamide as a template and by a template-free method (Si/Al = 24). The morphology, textural, and acidic properties of the synthesized zeolites have been studied by scanning electron microscopy, high-resolution transmission electron microscopy, N2 adsorption, IR spectroscopy of adsorbed pyridine, and temperature-programmed desorption of ammonia and compared with the properties of a commercial ZSM-23 zeolite (Si/Al = 24). Zeolite powders have been used to prepare ZSM-23+Al2O3 supports and then Pt-modified bifunctional catalysts, the properties of which have been tested in n-decane hydroconversion. It has been shown that the isomerization activity of the Pt/ZSM-23/Al2O3 catalysts is largely determined by the texture and morphology of the original zeolites.

The influence of the composition and structure of copolymers based on fluoroalkyl methacrylates with a low fluorine content in the monomer unit (from 3 to 7 atoms) on the stability of the superhydrophobic state in the mode of heterogeneous wetting of the surface of grade 304 stainless steel, which was preliminarily etched in hydrofluoric acid, is studied. The characteristics of the hierarchical texture of the steel surface, in particular, the depth of etching and penetration of polymer modifiers, are investigated. Superhydrophobic polymer coatings on stainless steel remain in the heterogeneous wetting regime for more than two days when a droplet of water is in continuous contact with the surface of the sample under saturated conditions: the contact angle changes from 168° to 155°.

The problem of optimizing the textural characteristics and chemical composition of the alumina support of a vacuum gasoil hydrotreating catalyst is considered. The catalyst is synthesized using the state-of-the-art environmentally friendly technology of flash calcination of gibbsite. Ways of increasing its specific surface area by introducing inorganic additives containing boron or sulfur at the stage of synthesizing boehmite with needle-shaped particles are developed. It is established that introducing such modifiers raises SBET by 50–100 m2/g, relative to the maximum values that can be attained by varying the standard parameters of hydrothermal treatment. It is shown that introducing boron at the stage of boehmite synthesis improves the catalytic activity of CoNiMoP catalyst in the hydrodesulfurization and hydrodenitrogenation of vacuum gasoil by two or more times, relative to a similar catalyst doped with boron from an impregnating solution.

CoMo-hydrotreating catalysts differed in the way of P addition were studied. The phosphorus was added in catalysts as follows: into the kneading paste of an alumina support, by impregnation of an alumina support before impregnation by active metals and into impregnation solution jointly with active metals. Impregnating solutions, supports and catalysts were studied by the nitrogen adsorption-desorption, UV–vis spectroscopy, RAMAN and ATR-FTIR spectroscopies, HRTEM, EDX, XPS. Catalysts were tested in hydrotreating of model feed. It was established that adding of P into the kneading paste or by impregnating of a support influenced negatively catalytic activity. Negative effect was caused by the formation of CoAl2O4 compounds and reduced portion of cobalt in the content of active phase. The addition of phosphorus into impregnation solution results in a significant increase in catalytic activity in the hydrodesulfurization of dibenzothiophene. In this case, phosphorous results in the change in the structure of active component precursors, the increase in the stacking number of the active component particles, the decrease in the interaction between active metals and a support. It was shown that the most efficient way to improve catalysts by P is to add its precursor into impregnating solution.

The effect of ultrastable zeolite Y recrystallization on the properties of NiMo/USY-Al2O3 hydrocracking catalyst has been studied. The mesoporosity, being introduced as the result of zeolite Y recrystallization, is mainly preserved at the subsequent steps of NiMo catalysts preparation. The total concentration of Bronsted acid sites in the catalysts varies proportionally to that for the corresponding zeolites used for preparation. It is observed that the higher the recrystallization degree the lower the concentration of strong Bronsted acid sites in the catalysts. UV–vis DRS, HRTEM and XPS data suggest that the state of supported Ni and Mo is similar for the catalysts prepared with parent and recrystallized zeolites. The catalysts based on recrystallized zeolites have significantly higher activity in hexadecane hydrocracking as compared to the catalyst obtained using parent zeolite. This effect is rationalized in terms of the improved accessibility of zeolite acid sites after recrystallization. Moreover, the mesoporosity introduced by zeolite Y recrystallization has a positive effect on the selectivity of NiMo/USY-Al2O3 hydrocracking catalyst.

Calcined CoMo/γ-Al2O3 hydrotreating catalysts were reactivated by a solution of citric acid and triethylene glycol. The reactivated catalysts were tested in HDS of dibenzothiophene and hydrotreating of SRGO. The reactivated catalysts were showed a significant increase in activity compared to calcined. The highest reactivation was observed for the sample reactivated using a solution of citric acid and triethylene glycol. All catalysts were characterized by means of UV-DRS, FTIR, Raman spectroscopy, XRD, XPS, and HTREM. It has been shown that the addition of triethylene glycol increases the proportion of CoMoS phase and the dispersion of sulfide particles.

Chitosan acylation with 2-bromoisobutyryl bromide in dimethylformamide was studied to obtain a macroinitiator for the subsequent synthesis of graft copolymers of chitosan with trimethyloxyethylmethacryloylammonium methyl sulfate using Atom Transfer Radical Polymerization. The acylation reaction under heterophase conditions is a distinctive feature of the proposed approach. The advantages of this approach are the ease of obtaining a macroinitiator and zero destruction of chitosan samples. This will allow to obtain high molecular weight copolymers of chitosan. In this work, chitosan samples with different molecular weight (ranging from 110 to 260 kDa) and degree of deacetylation (80–92%) were studied. Elemental analysis, IR spectroscopy, and energy-dispersive analysis have shown that the acylation reaction proceeds via the NH2 group, because it is most reactive. Regardless of the molecular weight and degree of deacetylation, the degree of acylation is 76–99% with the optimal synthesis time of 1 day. Due to the extremely high sensitivity to contamination of the reaction and of the subsequent polymerization reaction, special attention is paid to the preparation of initial chitosan samples (i.e., purification from unreacted chitin and various impurities). The presented results on obtaining chitosan macroinitiator are novel and serve as the basis for the synthesis of graft copolymers of chitosan using Atom Transfer Radical Polymerization with a variable hydrophilic–lipophilic balance.

Under discussion is optimization of texture and chemical composition of alumina as the support for the catalyst for hydrotreatment of vacuum gasoil synthesized using the environmentally friendly modern technology of flash thermal treatment of gibbsite. Approaches to increasing the specific surface area by introducing inorganic admixtures (including boron or sulfur) at the stage of synthesis of pseudoboehmite were developed. The introduction of these modifiers was established to increase SBET by 50–100 m2/g comparing to the maximal areas attaineddue to variation in the standard process parameters of the hydrothermal treatment. It was shown that the introduction of boron at the stage of pseudoboehmite synthesis resulted in no less than two times increase in the catalytic activity of CoNiMoP to hydrodesulfurization and hydrodenitrogenation against the activity of a similar catalyst with boron introduced with the impregnating solution.

NiMo/γ-Al2O3 protective-layer catalysts for removing silicon from diesel fractions were examined. The catalysts differ in the way in which boron is introduced into the support. The supports and catalysts were examined by X-ray diffraction analysis, transmission electron microscopy, IR spectroscopy, and adsorption–desorption of nitrogen. The catalysts were tested in hydropurification of the diesel fraction to which decamethylcyclopentanesiloxane was added as a model silicon compound. It was shown that introduction of boron into the support results in that the surface area of the supports and catalysts increases. If boron is introduced into pseudoboehmite, massive particles of the Ni–Mo–S phase are formed. It was found that the highest capacity for silicon is observed for the catalyst into which boron is introduced in the stage of pseudoboehmite preparation.

Chitosan is one of promising polymer from natural polysaccharides, which is an environmentally friendly compound from renewable raw materials. Chitosan has biodegradability, biocompatibility, and exhibits antimicrobial, antibacterial, and other activities. In this article, we report the first use of copolymers based on glycidyl methacrylate and (fluoro)alkyl methacrylates as material surface wettability modifiers based on a chitosan, and we show that grafting of copolymers allows an increase in the hydrophobicity of films with contact angles up to 114° and up to 154° for aerogels. The resulting chitosan aerogels have high porosity with a pore size of 100–200 µm and the pore walls are 0.6–0.7 µm-thick film formations. Our study of lyophilic properties of modified chitosan substrates showed a change in the hydrophobicity of the materials as a function of length of the hydrocarbon radical in the side groups of (fluoro)alkyl methacrylates in the copolymers. Additionally, the rate of biodegradation of the resulting materials decreased with an increase in the number of hydrophobic groups in the modifier. Obtained chitosan materials with hydrophobic coatings have potential as a protective layer for wound dressings with an extended service life.

A series of low-sodium ultrastable Y zeolites (SiO2/Al2O3 ≈ 25) partially exchanged with different amounts of rare earth ions (RE2O3 = 0.55–3.32 wt%) was prepared and characterized by XRD, IR spectroscopy, elemental analysis, N2 adsorption, as well as 29Si and 27Al NMR. The effect of RE content on the number and relative strength of acid sites of REY zeolites was studied by IR spectroscopy of absorbed CO and pyridine. The increase in the RE content in the zeolites leads to a decrease in the concentration of strong Bronsted acid sites (BAS) in faujasite cages (bridged Si–O(H)–Al groups), especially the concentration of stronger BAS associated with Si–O(H)–Al groups polarized by extra-framework aluminum species. At the same time, the concentration of less acidic OH groups connected with extra-framework ions increases possibly due to the formation of additional RE–O(H)–Al groups. The total number of BAS in all the samples remains close. An increase in the RE2O3 content from 0.55 to 3.32 wt% decreases almost by half the ratio of strong BAS in faujasite cages to less acidic extra-framework BAS. The catalytic performance of NiMo/(30 wt% REY + 70 wt% Al2O3) catalysts was evaluated in hydrocracking of vacuum gas oil. The enhanced hydrocracking activity and selectivity to middle distillates are mainly achieved due to the optimal acidity of the zeolites.

A NiMoP/Al2O3 catalyst deactivated at the industrial plant was subjected to oxidative regeneration and reactivation with water and an aqueous solution of citric acid. The catalyst was studied at all stages by XRD, UV-vis, Raman spectroscopy, FTIR spectroscopy, XPS and HRTEM methods. The catalyst samples after oxidative regeneration, treatment with water and rejuvenation with citric acid were tested in hydrotreatment of the model feedstock and straight-run gasoil. It was established that the regenerated catalyst contained phosphorus strongly bound to the support and soluble or insoluble Ni and Mo compounds. The catalyst after water treatment contained only insoluble Ni and Mo compounds and a phosphate monolayer, while treatment with citric acid resulted in the formation of citrate complex compounds. Ni and Mo compounds in the sulfide form, which were obtained from insoluble components, showed high activity in the target hydrotreating reactions.

CoMoB/Al2O3 catalysts with up to 2 wt.% of B have been synthesized by two different methods an introduction of boron into γ-Al2O3 support during the kneading of the paste or by the impregnating of γ-Al2O3 extrudates by the solution of Mo and Co compounds, citric and boric acids. It is shown that the activity in HDS and HDN of diesel fuel increases with increasing boron content in catalysts. The growth of the activity is associated with the increase in CoMoS phase content, Co dispersity, an average slab length of sulfide active component particles and an average number of slabs per 1000 nm2. The positive effect of boron is much more pronounced for catalysts prepared by the introduction of boron to the solution, since boron is located preferentially on the surface of alumina particles.

In the present work, NiW/Al 2 O 3 catalyst was prepared with the use of citric acid and thermally treated at temperatures of 120, 220, 300 and 450 °C. It was shown that the thermal treatment at temperatures of 220–300 °C leads to decomposition of citrate ligands, 450 °C – to the almost complete removal of organic carbon. HRTEM of the sulfided catalysts showed that stacking number of WS 2 increases with the increase of the thermal treatment temperature while the WS 2 slab length has minimum at 220 °C. The results of XPS indicated that the sulfidation degree of tungsten and nickel decreases with the increase of the thermal treatment temperature. The catalyst thermally treated at 300 °C resulted to be most active in DBT HDS, quinoline HDN and naphthalene hydrogenation reactions. The higher activity of this catalyst in comparison with the samples thermally treated at 120 °C and 220 °C can be explained by an increased stacking degree of the sulfide WS 2 slabs while maintaining a small length of sulfide slabs and by a smaller carbon content that can impede access to the active sites. The calcination at 450 °C leads to low activity due to the low dispersion of the active component and a decrease in the degree of sulfidation of tungsten and nickel.

Absract CoMo/Al2O3-ASA catalysts with Mg were synthesized. Catalysts differed in the way of Mg addition: 1. Mg was added to ASA, 2. Mg was added to the kneading paste during the support preparation, 3. Mg was added before or after Co and Mo by the impregnation. Catalysts were characterized by the following techniques: low-temperature N2 adsorption, IR of CO and CO2 adsorption, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy. Synthesized catalysts were tested in hydrotreating of the model fluid catalytic cracking gasoline containing 250 ppm of sulfur from thiophene, 40 wt.% of toluene, 40 wt.% of heptane and 20 wt.% of n-hexene-1. It was found that the addition of Mg resulted in changes of physico-chemical properties of catalysts and their HDS and HYD activities. The way of Mg addition influenced the content of Lewis and Bronsted acid sites and morphology of sulfide active component. Mg increased HDS activity and decreased octane number loss. The catalysts with Mg in the kneading paste of the support and with Mg added after active metals showed the best combination of HDS activity and selectivity.

Commercial liquid-phase-sulfided type II CoMo/Al2O3 catalyst was reactivated after commercial operation and oxidative regeneration. For this purpose, the use of citric acid (CA) that reactivates a regenerated CoMo/Al2O3 catalyst was studied. The study of the reactivated catalyst was carried out by means of UV-DRS, FTIR, Raman spectroscopy, XRD, XPS, and HTREM. The catalytic activity was estimated in the HDS of straight-run gasoil (SRGO). It was shown that the treatment of the catalyst with CA leads to the formation of a Co–Mo complex compound and significantly reduces the proportion of β-CoMoO4 and MoO3 in the catalyst. Eventually, this leads to the formation of CoMoS phase type II in a higher proportion enhancing the HDS catalytic properties.

The effect of the conditions of bituminous sand hydrogenation on the yields and properties of the resulting liquid hydrocarbons was studied. It was found that, on the hydrogenation of bituminous sand, hydrocarbon products of higher quality can be obtained with a higher yield, as compared with the products of pyrolysis. The conditions affording a maximum yield of synthetic oil or an increased yield of light hydrocarbons were determined.

In this study, we presented a new approach for quantification of bicarbonate (HCO3-) molecules bound to PSII. Our method, which is based on a combination of membrane-inlet mass spectrometry (MIMS) ...

Ni-Mo bimetallic catalysts are prepared by impregnating a carrier containing amorphous aluminosilicate (AAS) and aluminum oxide using a solution with Ni, Mo, and citric acid. The temperature of the catalysts ranges from 120 to 550°С. The physicochemical properties of the catalysts are studied via XPS, TEM, and HCNS analysis, and they are tested in hydrocracking of vacuum gasoil. The particles of the sulfide active component (NiMoS phase) are localized predominantly on surfaces of aluminum oxide, and only some are on surfaces of AAS. When the temperature of catalyst calcination is raised, the average number of the layers in particles of the NiMoS phase grows as well, due to the removal of citric acid. This indicates strengthening of the interaction between the sulfide active component and aluminum oxide. The content of Ni-Mo massive sulfide particles also grows along with the temperature of calcination. The morphological characteristics of the sulfide active component affect the activity of the catalysts in hydrodesulfurization and hydrodenitrogenation, but not in hydrocracking. The optimum heat treatment temperature for NiMo/AAS-Al2O3 catalysts prepared with citric acid is 120°C. Recommendations are given for the heat treatment of catalysts under industrial conditions.

The effect of the hydrogenation temperature of oil shale from the Kashpir deposit on the yield and the properties of the resulting liquid hydrocarbons and gasoline and diesel fractions separated from them was studied. It was found that synthetic oil can be obtained from high-sulfur oil shale with the use of hydrogenation processing. In this case, it is possible to extract more than 90% of the organic matter of oil shale. Depending on the temperature of this processing, the sulfur content of the synthetic oil varied from 2.8 to 4.2 wt %, and the nitrogen and light fraction contents varied from 1.3 to 1.6 and from 34 to 67 wt %, respectively.

The effect of the W: (W + Mo) atomic ratio in NiMoW trimetallic catalysts on their catalytic and physicochemical properties is studied. The catalysts are prepared by impregnating a carrier containing amorphous aluminosilicate (AAS) and aluminium oxide with an aqueous solution containing Ni, Mo, W compounds, and citric acid. They are studied via XRF, TEM, NH3 TPD, and low-temperature nitrogen adsorption and are tested in the hydrocracking of vacuum gasoil (VGO). The average length of a sulfide active component layer shrinks as the amount of Mo increases and the amount of W in the catalyst is reduced. XPS data indicate that the degree of sulfidation of tungsten in NiMoW trimetallic catalysts is lower than in NiW catalyst. Testing of the catalysts in hydrocracking of a straight-line VGO at 390–420°C, 16 MPa, a feedstock hourly space velocity (FHSV) of 0.71 h−1, and a H2: VGO ratio of 1200 L/L shows the activities of hydrodesulfurization, hydrodenitrogenation, hydrogenation, and hydrocracking grow along with the W: (W + Mo) ratio. When the process pressure is high and the amount of sulfur in the NiW feedstock is low, the catalysts have higher activity in the target reactions of VGO hydrocracking than NiMo catalyst.

The hydroconversion of high-sulfur oil shale in the presence of natural mineral matrices: shale ash, sandstone, and clay has been investigated. It has been shown that mineral matrices containing clays and iron exhibit catalytic activity during the hydroconversion of oil shales. Due to this activity, a significant reduction in the sulfur and nitrogen content and an increase in the amount of light fractions in the resulting synthetic oil are achieved.

This study involved the modification of a textured aluminum surface with reactive fluoroalkyl methacrylate copolymers with short-chain fluoroalkyl radicals and glycidyl methacrylate to achieve superhydrophobic properties. The resulting grafted polymer coatings are characterized by contact angles up to 170° and roll-off angles of 2–3°. The multimodal texture of the modified aluminum surface layer, namely, the etching depth and the penetration depth of polymeric modifiers, has been investigated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). This study demonstrates an increase in the stability of the heterogeneous wetting regime of superhydrophobic coatings based on fluoroalkyl methacrylate copolymers due to multiple attachment of the polymeric modifier to the surface.

We propose a novel approach to create a superhydrophobic coating on an aluminum surface by attaching random copolymers that are based on glycidyl methacrylate and a number of fluoroalkyl methacrylates that contain 3–7 fluorine atoms in their monomer units. To texture the aluminum surface, short-term etching with hydrochloric acid solutions was used. The coatings that are based on glycidyl methacrylate and fluoroalkyl methacrylate copolymers maintain superhydrophobic properties for longer than 40 h under saturated vapor conditions.

Effect of various chelating components, multibasic carboxylic acids and glycols, used to prepare hydrotreating catalysts on the activity regeneration of calcined hydrotreating catalysts was studied. Reactivated catalyst samples were tested in a model reaction of hydrodesulfurization of dibenzothiophene. It was shown that the treatment of calcined catalysts with the chelating components leads to an increase in the catalytic activity. The best catalytic characteristics are observed for the catalyst reactivated with a solution containing citric acid and triethylene glycol.

A quantitative topological analysis of supramolecular structures in ethanol solutions with methanol, propanol, water, benzene, and hexane is performed by the MDGT method previously proposed by the authors. The method is based on a combination of molecular dynamics calculations and the graph theory, which enables the recognition and memorization of supramolecular structures observed in each snapshot of the molecular dynamic trajectory, the averaging of data for any number of these snapshots. Thus, the averaged concentrations of associates (dimers, trimers, etc.) are represented and then the concentrations and characteristics of isomers (e.g., chains, branched chains, rings, etc.), bond lengths, angles, etc. are determined in each group of associates.

This study describes a new role for hydroperoxide lyase branch of oxylipin biosynthesis pathway in protecting photosynthetic apparatus under high light conditions. Lipid-derived signaling molecules, oxylipins, produced by a multi-branch pathway are central in regulation of a wide range of functions. The two most known branches, allene oxide synthase (AOS) and 13-hydroperoxide lyase (HPL) pathways, are best recognized as producers of defense compounds against biotic challenges. In the present work, we examine the role of these two oxylipin branches in plant tolerance to the abiotic stress, namely excessive light. Towards this goal, we have analyzed variable chlorophyll fluorescence parameters of intact leaves of Arabidopsis thaliana genotypes with altered oxylipin profile, followed by examining the impact of exogenous application of selected oxylipins on functional activity of photosynthetic apparatus in intact leaves and isolated thylakoid membranes. Our findings unequivocally bridge the function of oxylipins to photosynthetic processes. Specifically, HPL overexpressing lines display enhanced adaptability in response to high light treatment as evidenced by lower rate constant of photosystem 2 (PS2) photoinhibition and higher rate constant of PS2 recovery after photoinhibition. In addition, exogenous application of linolenic acid, 13-hydroperoxy linolenic acid, 12-oxophytodienoic acid, and methyl jasmonate individually, suppresses photochemical activity of PS2 in intact plants and isolated thylakoid membranes, while application of HPL-branch metabolites—does not. Collectively these data implicate function of HPL branch of oxylipin biosynthesis pathway in guarding PS2 under high light conditions, potentially exerted through tight regulation of free linolenic acid and 13-hydroperoxy linolenic acid levels, as well as competition with production of metabolites by AOS-branch of the oxylipin pathway.

An approach to making the surface of a cotton cloth possessing superhydrophobic properties is given consisting in graft polymerization of fluoroalkyl metacrylates by the atom transfer radical polymerization method (ATRP). Poly(glycidyl methacrylate) was used as an anchor layer, followed by fixing of the polymerization initiator. The stability of the hydrophobic properties of the modified cloth under prolonged contact with aqueous media and organic solvents was demonstrated.

Photosynthesis in tissues under periderm of woody stems and shoots of perennial plants occurs in environment that is very different from the internal environment of leaf chloroplasts. These tissues are characterized by high CO2 and low O2 concentrations, more acidic surroundings, besides that only light which have passed through periderm reaches photosynthetic antennas. In contrast to leaves of deciduous plants chlorenchyma tissues of wintering plant organs are exposed to temperature fluctuations during all seasons, that is why the photosynthetic apparatus of woody stems has to be able to adapt to a wide range of environmental temperatures. In order to reveal unique features, which enable photosynthetic apparatus of chlorenchyma cells in woody plant organs to implement biological functions under different light and temperature conditions, we studied photosynthetic tissues of stem cortex in grapevine (Vitis vinifera L.) under normal conditions and after exposure to suboptimal temperatures and high light intensity. Comparative analysis of photosynthetic pigment composition and low-temperature chlorophyll fluorescence emission spectrum of leaves, young shoots and chlorenchyma of lignified shoots revealed relatively high level of chlorophyll b and carotenoids, and high photosystem II (PSII) to photosystem I (PSI) ratio in woody shoots. Analysis of parameters of variable chlorophyll fluorescence revealed high PSII activity in grapevine shoot cortex and demonstrated improved freeze tolerance and higher sensitivity to light of photosynthetic apparatus in grape vine in comparison to leaves. It was shown for the first time that photosynthetic apparatus in chlorenchyma cells of vine undergoes so-called “state-transition”–fast rearrangements leading to redistribution of energy between photosystems. Analysis of fatty acid (FA) compositions of lipids in examined tissues showed that the FA unsaturation index in green tissue of vine is lower than in leaves. A distinct feature of FA compositions of lipids in vine cortex was relatively high level of linoleic acid.

Recently, it has been shown that the addition of 1 M trehalose leads to the increase of the rate of oxygen photoconsumption associated with activation of electron transport in the reaction center of photosystem 2 (PS2) in Mn-depleted PS2 membranes (apo-WOC-PS2) [37]. In the present work the effect of trehalose on photoinhibition of apo-WOC-PS2 preparations (which are characterized by a high sensitivity to the donor side photoinhibition of PS2) was investigated. The degree of photoinhibition was estimated by the loss of the capability of exogenous electron donor (sodium ascorbate) to reactivate the electron transport (measured by light-induced changes of chlorophyll fluorescence yield (∆F)) in apo-WOC-PS2. It was found that 1 M trehalose enhanced the Mn2 +-dependent suppression of photoinhibition of apo-WOC-PS2: in the presence of trehalose the addition of 0.2 μM Mn2 + (corresponding to 2 Mn2 + per one reaction center) was sufficient for an almost complete suppression of the donor side photoinhibition of the complex. In the absence of trehalose it was necessary to add 100 μM Mn2 + to achieve a similar result. The effect of trehalose was observed during photoinhibition of apo-WOC-PS2 at low (15 μmol photon s− 1 m− 2) and high (200 μmol photon s− 1 m− 2) light intensity. When Mn2 + was replaced by other PS2 electron donors (ferrocyanide, DPC) as well as by Ca2 + the protective effect of trehalose was not observed. It was also found that 1 M trehalose decreased photoinhibition of apo-WOC-PS2 if the samples contained endogenous manganese (1–2 Mn ions per one RC was enough for the maximum protection effect). It is concluded that structural changes in PS2 caused by the addition of trehalose enhance the capability of photochemical reaction centers of apo-WOC-PS2 to accept electrons from manganese (both exogenous and endogenous), which in turn leads to a considerable suppression of the donor side photoinhibition of PS2.

The effect of the addition of boric and phosphoric acids to impregnating solutions on the structure and properties of NiMo catalysts for VGO hydrotreating was studied. The catalysts contained a wide-porous support on the basis of a mixture of γ- and δ-Al2O3 phases. The catalysts were studied by XRD, HRTEM, IR CO, ATR-FTIR, XPS. The catalytic activity was evaluated in hydrotreating of heavy VGO. It is established that the NiMo-citrate complex is formed in impregnating solutions. At the same time, the introduction of phosphoric and boric acids into NiMo-citrate complex solution does not lead to a distortion of the complex compound structure. It has been found that calcining of the support at 900 °C makes it possible to obtain a mixture of gamma and delta phases. It was determined that phosphoric and boric acids react with OH groups of the support, but the introduction of phosphoric acid leads to the formation of P OH groups on the surface. The presence of P and/or B in a catalyst composition results in an increase in the number of MoS2 layers in a slab. However, with the introduction of B, a small decrease in the amount of Mo on the surface of a catalyst in the form of Mo4+ is observed. The change in textural and acid characteristics allows us to conclude that bulk particles of BO3 are formed. Testing of catalysts in hydrotreating of heavy VGO made it possible to establish that the introduction of B into composition of the impregnating solution significantly reduces the activity of the catalysts in hydrotreating, while the introduction of phosphorus leads to an increase in the activity of a catalyst. The introduction of phosphoric and boric acids into the impregnating solution simultaneously increased the activity of the catalyst as compared to the sample containing boron only.

The positive effect of alumina surface graphitization by CVD with ethylene on the activity of CoMo catalysts in hydrodesulfurization has been demonstrated. X-ray diffraction, Raman spectroscopy, High-resolution transmission electron microscopy, X-ray photoelectron spectroscopy and nitrogen physisorption showed that alumina surface graphitization does not significantly change the morphology and textural characteristics of the support. However, it has a significant impact on the morphology of supported sulfide component resulting in the formation of particles with a shorter slab length (2.9 vs 3.3 nm) and higher stacking number (2.4 vs 2.1) as compared to the sample based on γ-Al2O3. The results of CoMoS/γ-Al2O3 and CoMoS/C@γ-Al2O3 catalysts testing in hydrotreating reactions demonstrated a similar activity in hydrodenitrogenation of quinoline and 1.7 times higher activity of CoMoS/C@γ-Al2O3 in hydrodesulfurization of dibenzothiophene. Higher hydrodesulfurization activity of CoMoS/C@γ-Al2O3 sample is attributed to improved dispersion of the supported sulfide component and enhanced promotion of MoS2 by cobalt. Thus, the simple CVD approach presented here allows selective modification of the surface of commercially available alumina supports with a layer of graphite-like carbon and can be used to improve the activity of conventional hydrotreating catalysts.

Modification of cotton fabric surface by random or block copolymers of glycidyl methacrylate and lauryl methacrylate is studied. It is shown that a cotton fabric surface modified in such a way takes on superhydrophobic properties and differs in stability under long-term contact with aqueous media.

It has been shown earlier (Khorobrykh and Klimov, 2015) that molecular oxygen is directly involved in the general mechanism of the donor side photoinhibition of photosystem II (PSII) membranes. In the present work the effect of oxygen on photoassembly ("photoactivation") of the functionally active inorganic core of the water-oxidizing complex (WOC) in Mn-depleted PSII preparations (apo-WOC-PSII) in the presence of exogenous Mn(2+), Ca(2+) as well as ferricyanide was investigated. It was revealed that the efficiency of the photoassembly of the WOC was considerably increased upon removal of oxygen from the medium during photoactivation procedure using the enzymatic oxygen trap or argon flow. The lowering of O2 concentration from 250μM to 75μM, 10μM and near 0μM results in 29%, 71% and 92%, respectively, stimulation of the rate of O2 evolution measured after the photoactivation. The increase in the intensity of light used during the photoactivation was accompanied by a decrease of both the efficiency of photoassembly of the WOC and the stimulation effect of removal of O2 (that may be due to the enhancement of the processes leading to the photodamage to PSII). It is concluded that the enhancement in photoactivation of oxygen-evolving activity of apo-WOC-PSII induced by oxygen removal from the medium is due to the suppression of the donor side photoinhibition of PSII in which molecular oxygen can be involved.

Bifunctional catalysts Pd/ASA-Al2O3, Pd/Y-ASA-Al2O3, Pd/Beta-ASA-Al2O3, Pd/ZSM-23-ASA-Al2O3 were prepared. Catalysts were characterized by FTIR of adsorbed CO, nitrogen adsorption and CO chemisorption. Average sizes of palladium particles in the catalysts were found to be 1.2–2.9 nm. Zeolite-based catalysts contained stronger Bronsted acidic sites than amorphous silica-alumina (ASA) based catalyst Pd/ASA-Al2O3. Catalysts were tested in hydroconversion of hydrocracker bottom (HCB). Hydrocracking activities of Pd/Y-ASA-Al2O3 and Pd/Beta-ASA-Al2O3 catalysts were found to be significantly higher than that of Pd/ASA-Al2O3 and Pd/ZSM-23-ASA-Al2O3 catalysts. Conversion of 80% of HCB was achieved for catalysts with zeolites beta and Y at 250 °C. It was found that selectivity to middle distillates increases in following order: Pd/ZSM-23-ASA-Al2O3

Measuring the quantity and composition of sinking particulate matter is key to understanding biogeochemical processes in the ocean. This has been done in the past with sequencing sediment traps, which collect and store particulate matter in sample bottles for subsequent laboratory analysis. Having a limited number of bottles, these traditional traps force the user to choose between finer time resolution and longer deployment duration. We have built a new sediment trap that analyzes the collected material in situ, eliminating the need to preserve and store the samples. This new instrument, the Sedimentation Event Sensor (SES), captures macro images of the sample with front and back lighting, and takes fluorometric measurements in two bands as proxies for the presence of chlorophyll a and accessory pigments. The SES can process 6200 samples during a single deployment, which is the equivalent of 15 samples per day for more than a year. Here, we describe the design of the SES and present the results of its first three deployments at 3910 m depth. Images and fluorometry data revealed high variability of sinking particulate matter composition on the order of hours. Sedimentation patterns detected by the SES largely agreed with mass flux patterns measured from traditional traps deployed concurrently nearby. Given the functional differences, the SES is best used to complement rather than replace traditional sediment traps.

The conversion of black oil in hydrogen (hydroconversion) and nitrogen (pyrolysis) media was studied. The influence of the hydrogen pressure and temperature of the hydrotreating of black oil on the yield and properties of the resulting liquid hydrocarbons was examined. Hydrogen actively participates in the conversion of kerogen (major organic component of black oil), which leads to an increase in the conversion of the organic matter, to an increase in the yield of liquid hydrocarbon products, and to improvement of their quality, compared to pyrolysis. The highest conversion of organic carbon (91.7%) and the maximal yield of liquid hydrocarbons (30.7 wt %) were reached in a hydrogen medium at a pressure of 10.0 MPa and a temperature of 400°C.

Procedures are suggested for preparing NiW/Al2O3 catalysts using ammonium paratungstate as a tungsten source and citric acid and D(+)-sorbitol as chelating agents. The catalysts prepared using the suggested reagents are characterized by increased dispersity of the sulfide component compared to the NiW/Al2O3 catalyst prepared by the traditional procedure using ammonium metatungstate and nickel(II) nitrate. In transformations of dibenzothiophene, quinoline, and naphthalene, the NiW/Al2O3 catalysts prepared using ammonium paratungstate and citric acid or D(+)-sorbitol considerably surpass in the activity the NiW/Al2O3 catalyst prepared by the traditional procedure.